Flexible plastic pipe, such as cross-linked polyethylene (PEX) pipe, is now widely used for hot and cold water plumbing systems, hydronic radiant heating systems, refrigeration systems and sprinkler systems. Various operations and tools are typically used with these types of pipes. For example, the pipes are generally connected using various connection fittings in order to split the flow through the pipe, to change a length of an existing pipe flow path or run, to make short turns in the pipe path, to change from one size of pipe to another, to cap or plug pipe ends, and so on. As with other pipes, the lengths of flexible plastic pipe may be connected by fittings such as unions, elbows, tees, crosses, reducers and the like. Most flexible plastic water pipe applications in the United States and Canada use pipe sizes of ⅜ inch, ½ inch, ⅝ inch, ¾ inch or 1 inch nominal designations. The most prevalent sizes are ½ inch, ¾ inch and 1 inch.
In addition to connections, there may be other operations when using flexible plastic pipe. For example, the pipe may be cut to a desired length, connection assemblies may need to be removed to make changes or to correct mistakes in installation, and connections may need to be measured or gauged to assure that the connections have been made properly to prevent leaking. One of the most common techniques for connecting plastic flexible pipe to a fitting is by using fittings that are pushed inside the end of the pipe. At the same time, a metal ring or sleeve is placed on the section of pipe that surrounds the fitting, and the ring is squeezed into a smaller diameter using a tool specially designed for that purpose. Fittings typically have circumferential ridges along the section that fits inside the pipe, and the pipe is squeezed onto these ridges to make a watertight seal. Herein, the ring or sleeve squeezing with a tool is referred to as compressing and the tool that is used to squeeze the ring or sleeve is referred to as a compression tool.
There are generally three types of compression rings or sleeves that are used to connect flexible plastic pipe to the fittings: 1) copper rings (CR); 2) stainless steel sleeves (SSS); and 3) stainless steel clamps (SSC). FIG. 1 illustrates representatives of each of the three types of compression rings or sleeves in their various sizes. Naturally, rings or sleeves of an increased size are used to fit larger pipe sizes. The ring or sleeve typically fits snugly on the pipe before compression, and an outer diameter of the ring or sleeve is decreased by about four to eight percent after compression. The CR rings and SS sleeves may be squeezed all around circumferentially by tools such as those shown in FIG. 2. The CR rings or the SS sleeves may be squeezed by a tool with jaws having a small smooth interior diameter, or the SS sleeves may be squeezed by jaws have a central groove around the inside diameter of the jaws. There may be slightly raised sections, which are typically about 1/16 inch wide on compressed rings or sleeves where the jaws of the tool meet up front and back during closure. The tool shown in FIG. 2 is a common compression tool design that is similar to a modified bolt cutter tool. SSC rings may be pulled into a smaller diameter by clamping together the raised portion or clamp ear on the outside of the ring as seen in FIG. 3. The force that is used for compression of all types of rings or sleeves generally increases as the size of the pipe in the pipe fitting diameters increase.
Flexible plastic pipe may be cut by saws or by slicing using knife-edge tubing cutters. Some flexible plastic pipe cutting approaches may require several cutting strokes and/or rotation of the pipe about its axis as the pipe is being cut.
A flexible plastic pipe installer may occasionally find it necessary to disconnect the pipe in order to reconfigure an installation or to correct an installation mistake. For flexible plastic pipe installations that use compression rings or sleeves, the compression rings or sleeves may be cut and/or removed, and the pipe may also be cut in order to disconnect the installation. Cutting the rings or sleeves typically requires considerable force applied to the metal, and a sharp edge to cut a metal ring.
Compression of rings and sleeves, along with placing pipe on fittings and rings or sleeves on pipe, is the most frequent operation in flexible pipe installation. To assure that compressed rings or sleeves are sufficiently tight to prevent leaks, the compressed rings or sleeves may be measured with a compression gauge. It may be desirable to form the compressed ring or sleeve diameter such that it is round and not too tight to reduce or avoid damaging the pipe or the fittings. Therefore, compressed rings or sleeves may be measured with a gauge to ensure that the compressed ring or sleeve diameter is in the proper range, for example within +/−0.008 inch. This type of gauge is generally referred to as a “go no-go” gauge because it indicates whether or not the compressed ring or sleeve is within the range (or a “go”) or is outside of the range (or a “no go”).
Standards for flexible pipe ring compression may be found, for example, in The American Society for Testing and Materials International (ASTM international) sections such as ASTM F 876, ASTM F 877 and ASTM F 845 and American National Standards Institute NSF/ANSI 14-2008. Standards may be based on extensive leak testing under elevated pressure and temperature conditions. Typically, separate tools may be used for the flexible plastic pipe operations of connecting (compression), ring cutting, pipe cutting, and testing the pipe with a gauge. In addition, many flexible plastic pipe applications may use separate tools for each different sizes of pipe connection, i.e., ⅜ inch, ½ inch, ⅝ inch, ¾ inch and 1 inch compression tools. Moreover, separate tools may be used for each type of ring or sleeve, i.e., different tools may be used for CR rings, SS sleeves and SSC rings a plumber who installs all types and sizes of connections may require 8 to 15 or more different tools. In the case of CR rings and SS sleeves, the tool jaws may each enclose a different size of circle to accommodate each pipe size. Larger pipe sizes generally require increased mechanical advantage or more hand force to produce the higher compression or cutting forces. In some cases, the tool handle length and/or the mass of the tool may be increased for structural strength to accommodate larger pipe sizes. Thus, in addition to using many different types of tools, the tools may be very large and/or heavy.
Different tools for ring cutting and pipe cutting may have particular jaw, handle and cutting surface designs to accommodate different types of rings or sleeves or different sizes of rings or sleeves and pipes. Moreover, the gauges may be separate from the other tools and may use a separate opening for measuring the high and the low limits for each of the different diameter sizes of compressed rings or sleeves. For example, a “go no-go” gauge for gauging ½ inch, ¾ inch and 1 inch pipe rings or sleeves would typically have six separate openings.